A suspected activist of the outlawed Students Islamic Movement of India has been picked up by a joint team of Mumbai and Bihar police forces in connection with the July 11 serial train blasts and taken to Mumbai for further interrogation.

Ziauddin Ansari was taken into custody from a house in Phulwarisharif locality in Patna on Friday night and kept under detention, Patna Senior Superintendent of Police Kundan Krishnan said on Saturday.

He said the suspect was questioned for several hours at Phulwarisharif police station before being taken to Mumbai.

Asked whether Ansari was formally arrested before being shifted to Mumbai, Krishnan said, "I can only say that he was detained and then taken to Mumbai by the Anti-Terrorist Squad."

Ansari's detention followed an advisory from the ATS, which suspected his involvement in the July 11 serial blasts in commuter trains in Mumbai that killed over 200 people and injured hundreds of others.

Earlier, the ATS had arrested two suspects Mohammad Kamal and Khalid Aziz from Bihar's Madhubani district on July 21.